SOD Geomagnetic Observatory

The oldest routine task of SGO is the regular measurement of the
geomagnetic field. The measurements began on 1st January 1914 and
continue until today. The only gap in the time series is between
16th September 1944 and 1st January 1947 due to the destruction of the
observatory during the war.

The analog La Cour was in operation until 31st December 1995.
Nowadays digital data is produced in the variation room of the
observatory by a Danish fluxgate magnetometer (FGE),
a Polish torsion photoelectric magnetometer (TPM),
and a Russian TPM magnetometer.
Weekly measurements of the absolute magnetic field (D,I and F)
provide the base line control for magnetometers.